Actually communism is the Marxist ideal that means a society where one works according to capacity and gets according to his needs. it appears that Marx did not conceive of communism in a single country. He believed that communism can be only a world system. He wrote two books. Das capital and The communist manifesto. He appealed to workers of the world to unite as they have nothing to lose except their chains and have a world to win.
May be Communism has not worked. But Marxist thought has inspired many. Today the condition of labor in capitalist countries is not as bad as used to be a few centuries before. Now there are factory law, minimum wages act, maximum work hours, safety rules, welfare and accommodation facility to workers. This improvement in workers condition is also attributable to communist thought to a great extent. Now workers are not completely proletariat. Marx said that they have nothing to lose and have a world to win. But today they have much to lose as their condition is not so bad as used to be. Instead of class war, there is more cooperation between workers and capitalists.
However we can't say that communism has totally failed. Actually it is the people who manage. Also Soviet experience may not be the last experience and only model of communism. There can be other models also in future. It is also not necessary that future model may be known only as 'communism'. what is important is the urge for economic and social justice. Communism is the condition where every one works according to his capacity and gets according to his needs. There could be many ways to attain this. This may be compared to Indian motto- Vasudhev Kutumbukum (world is family). In a family, every one works according to capacity and gets according to need. Father works outside, mother in kitchen/ home and children go to school. But all get what they need. The same idea is applied to whole world- vasudhev Kutumbkum, which ultimately means 'communism'.